Pivotal guard for punch presses

ABSTRACT

This disclosure relates to a pivotal guard, particularly for punch presses and like machines, the guard including two side sections and a central pivotal section therebetween with abutments stopping the pivotal movement of the pivotal section in a direction away from a work area into which might be placed the hands of a worker thereby permitting the rapid removal of a worker&#39;&#39;s hand therefrom while simultaneously rendering it extremely difficult for the insertion of hands into the work area due to the provision of means for precluding pivotal movement of the pivotal section beyond a certain position in a direction toward the work area.

[451 Jul 29, 1975 United States Patent [191 Dopke et al.

[54] PIVOTAL GUARD FOR PUNCH PRESSES 3,368,479 2/1968 Gregorowich'............... lOO/DIG. I8 [75] 3,777,602 12/1973 Youra..................,....... IOO/DIG. 18

;. 60 b k 0 mm S MM 0 ow F i am S m MB J d an mh e JL s r o t n e V n I Primary ExaminerBenjamin W. Wyche Assistant Examiner-F. D. Shoemaker of [I].

[73] Assignee: Union Special Corporation, Chicago, A n y, g 0r Firm-Diner. Brown, Ramik &

m. Wight ABSTRACT This disclosure relates to a pivotal [22] Filed: Nov. 5, 1973 guard, particularly Appl.No.: 412,623

therebetween with abutments stoppi movement of the pivotal section in a from a work area into which m hands of a worker thereby perm 32 00 Em 016 P HM Un v 6 B ,3 m m 7 m W WW6 "4 NW mmh r "8 H L n C d l xm UIF HUM 555 [56] References Cited moval of a workers hand therefrom while simulta- UNITED STATES PATENTS neously rendering it extremely difficult for the insertion of hands into the work area due to the provision 74/612 of means for precluding pivotal movement of the i otal Section beyond a certain Position in a direction 74/612 toward the k area. 74/612 X 15 Claims, 4 Drawing Fig PIVOTAL GUARD FOR PUNCH PRESSES Several years ago, the U.S. Congress passed the Occupational Safety & Health Act which among its provisions require that a worker must not be able to insert his hands between the jaws of a poised power press or like machines. Prior to this legislation. and thereafter, intricate controls have been designed, and generally part of the overall system includes a guard of one type or another which encompasses the work area or the area in which the material which is to be worked upon by the particular machine in question is fed, either automatically or manually. In a typical press, a piece of metal is positioned upon a die carried by a bolster plate, and the latter components pass through an opening in a front section of the guard into the work area and return in a like though reverse manner. During such work cycle, it is not inconceivable, irrespective of precautions, for a workman to insert his hand through the opening in the front section of the guard for one reason or another, and in so doing risks dismemberment, disfigurement, or a like damage.

Should a worker so insert his hand into the work area and desire to remove it therefrom quickly when his error has been discovered, the access opening of the front guard section provides a limited opening for rapid hand removal. Thus, the guard actually is a detriment to safety once a workers hand has been inserted into the work area. Most notable among guards of this type are those which include rigid front sections which neither move inwardly toward or outwardly away from the work area. Hence, rapid withdrawal of a workers hand from the work area through such a limited access opening is extremely difficult. Moreover, since the withdrawal is basically an instinctive action, there is a tendency for a worker to not only draw his hand outwardly from the work area but also upwardly, and the latter motion would bring his hand into contact with the guard and thereby limit the speed of withdrawal.

In keeping with the foregoing, it is a primary object of this invention to provide a novel guard which not only makes it difficult for a worker to insert his hand or hands into a work area of a press or like machine, but also includes means for permitting his rapid withdrawal therefrom, the latter including the pivotal mounting of a front guard section.

A further object of this invention is to provide a novel guard of the type aforementioned in which the pivotal section is restricted during its pivoting movement in a direction away from the work area whereby full opening is precluded thus preventing a worker from opening the front or pivotal section totally in operating the machine in the absence of the protection intended to be provided thereby.

Still another object of this invention is to provide a novel guard of the type heretofore described wherein means are provided for precluding pivotal movement of the front or pivotal section beyond a certain position in a direction toward the work area thereby likewise preventing the pivotal guard to be positioned such that the normal minimal access opening can be enlarged, again providing additional safety.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing.

IN THE DRAWING:

FIG. 1 is a perspective view of a novel guard constructed in accordance with this invention and illustrates two side guard sections, a front pivotal guard section and means for limiting pivotal motion of the pivotal section in directions both toward and away from a work area as might, forexample, be defined by the area of descent ofa punch press ram and an aligned die carried by a sliding bolster plate.

FIG. 2 is an enlarged fragmentary side elevational view looking from right-to-left in FIG. 1, and illustrates the manner in which an arm carried by a rod of the pivotal section abuts a pair of pins to limit the pivotal motion of the pivotal section to approximately 15 degrees.

FIG. 3 is an enlarged sectional view taken generally along line 3-3 of FIG. I, and illustrates the manner in which the individual hairpin guards of the pivotal section can be adjusted to vary the size of an access openmg.

FIG. 4 is a fragmentary sectional view of a portion of the pivotal section, and illustrates the manner in which a tool is applied to spring clips for permitting adjustment of the hairpin guards.

A novel guard constructed in accordance with this invention for punch press or like machinery is illustrated in FIG. 1 and is generally designated by the reference numeral 10. The guard 10 is illustrated for convenience in combination with a machine bed 11 having a bolster plate 12 mounted thereon for reciprocable motion in the direction of the unnumbered doubleheaded arrow associated therewith. The bolster plate 12 is mounted in suitable guides or ways l3, l4 and is adapted to have secured to the upper surface thereof, a suitable die (not shown). The bolster plate 12 is illustrated in its endmost or forwardmost position and when thereat the ram (not shown) of the punch press descends to strike metal carried by the die (not shown). At the conclusion of this operation, the bolster plate is retracted out of the working area i.e. the area at which the die and punch are in alignment, the work is removed, another element is placed upon the die and the bolster plate 12 again moves into the work area. In accordance with this invention, the so-called work area is surrounded by the guard 10 and the purpose thereof is, of course, to preclude the introduction of a workers hand or hands thereinto, but should the latter occur the guard 10 is also designed to permit the rapid withdrawal of the workers hand or hands from this working area.

The guard 10 includes a pair of mounting blocks or pedestals 15, 16 which are secured to the machine bed 11 or the guides 14, 13 thereof by suitable bolts I7, 18.

Upstanding rods 20, 21 are secured to the blocks 15, 16, respectively, by bolts 22. The vertical rods 20, 21 carry blocks 23, 24 at upper ends thereof with the blocks 23,24 being secured to the respective rods 20, 21 by suitable bolts 25, 26. The blocks 23, 24 have bores 27, 28 for slidably receiving generally horizontally disposed rods 30, 31 of side guard sections 32, 33 respectively. The rods 30, 31 are circular in cross section and after being inserted in the bores 27, 28, the same may be locked in any desired position by screws 34. The rods 30, 31 include a plurality of circular holes 35, 36 which receive ends of narrow generally U- shaped guard elements or hairpin guards 37. The guards 37 are secured in a desired position of vertical adjustment by clips 38 which will be described more fully hereinafter with respect to FIG. 4 of the drawing.

Ends of the rods 30, 31 are received in bores 40, 41 of mounting blocks 12, 43, respectively. Suitable bolts 44 (FIG. 2) fasten the mounting blocks 42, 43 to the respective rods 30, 31. Identical aligned bores (unnumbered) of the blocks 42., 43 receive opposite ends of a cylindrical rod or bar 45. The rod 45 is thus mounted for pivotal movement within the bores of the blocks 42. 43 and is restrained against axial movement by thrust collars 46, 4'7 suitably secured thereto by. for example. a transverse set screw or the like. The bar or rod L likewise includes a plurality of parallel holes 48 which receive the upper ends of generally U-shaped elements or hairpin guards 49 which collectively define a front pivotal section 50 of the overall guard 10. The centermost four hairpin guards 49 are illustrated raised higher than each next adjacent hairpin guard to either side thereof and the latter are also slightly higher than the next adjacent two hairpin guards with all of the hairpin guards 49 being held in these positions by clips 38 thereby defining an access opening 0 between the bottom ends of the centermost hairpin guards and the upper surface of the bolster plate 12. The opening 0 is designed to permit the passage of the die and the workpiece into the work area while precluding the introduction of a workers hand thereinto. Thus. depending upon the size of the die and the work piece. the access opening 0 must be capable of being changed in size and in accordance therewith each clip 38 (FIG. 3) is of a generally U-shaped configuration with legs 50, 51 having respective apertures 52, 53 for receiving one leg of each hairpin guard 49 and curled or rounded ends 54,55. A pliers-like tool P (FIG. 4) has ends (unnumbered) contoured to the curls 54, 55 of the clips 38. When the handles H of the tool P are squeezed, the opposite ends thereof move toward each other resulting in the deflection of the clips 38 from the solid to the phantom outline position shown in FIG. 3. When so depressed, the hairpin guards 49 may be slid upwardly or downwardly as desired in the various holes 48 of the bars 45, 30 and/or 31 in the manner readily apparent from FIG. 3.

Inasmuch as the construction of the mounting blocks 42, 43 is identical, the mounting block 43 will be described in detail with its description equally applicable to the mounting block The mounting block 63 (FIG. 2) includes abutment means in the form of three pins 61, 62 and 63. An arm 64 having an end 65 disposed between the pins 61, 62 is secured to the rod 45 by an appropriate collar 66. A spring 67 connected between the pin 63 and the end 65 of the arm 64 biases the arm 64 normally into contact with the pin 62. This construction provides means for maintaining the front or pivotal section 50 vertical and precludes pivotal movement of the pivotal section 50 beyond this vertical position in a direction toward the work area or counterclockwise as viewed in FIG. ll. By so precluding further pivoting motion in the latternoted direction, the access area 0 cannot be increased in size by further inward pivotal motion and the opening as established by the hairpin guards 49 of the pivotal section 50 remains constant so long as the arm 64 is in contact with the pin 62 of both of the blocks 42 and 43.

Should a worker desire to remove a hand from the work area which may be placed therein inadvertently. it is highly desirable to provide an area larger than the 4 access opening 0 through which the worker's hand can be rapidly removed. In this case. the distance between the arm 64 and the pin 61, as shown in the position of FIG. 2. permits the pivotal guard 50 to be pivoted away from the work area. as indicated by the unnumbered headed arrows associated therewith in FIG. 1 until the arm 64 contacts the'pi'n 61. The are of travel is set at approximately 15 or generally the distance of motion of the arm 64 between the projections 61 and 62. Thus a worker actually provides a larger opening should he contact the pivotal section 50 upon the withdrawal of his hand from the work area and in effect causes an increase in the access opening to permit the rapid withdrawal of his hand therefrom. Of course. it is highly desirable not to permit excessive movement of the pivotal section away from the work area as a worker might tend to simply completely open the front section 50 and destroy the protection afforded or designed to be afforded by the front pivotal section 50. Therefore. the projection 61 serves as means for restricting the pivotal movement of the pivotal section 50 during its pivotal movement in a direction away from the work area.

thereby assuring design operability of the overall guard While one form of the invention has been shown for purposes of illustration.'it is to be understood that various changes in details and arrangement of parts may be made without departing from the spirit and scope of the invention as defined in the appended claimed subject matter.

We claim:

ll. A guard for machinery comprising means for at least partially encompassing an area into which might be placed the hand ofa worker. said area encompassing means includes a pivotal section. means mounting said pivotal section for free pivotal movement about a generally horizontal axis. first means for abuttingly stopping the pivotal movement of said pivotal section beyond a certain position during its pivoting movement in a direction toward said area. and second means for abuttingly stopping the pivotal movement of said pivotal section during its pivoting movement in a direction away from said area. g i

2. The guard as defined in claim '1"wh ereinsaid pivotal section has upper and lower ortions; and said mounting means pivotally mounts said upper portion whereby said lower portion is stopped by said first and second abuttingly stopping means in said directions toward and away from said area.

3. The guard as defined in claim 1 wherein the first and second abuttingly stopping means combiningly stop the pivotal movement of said section at generally 15.

t. The guard as defined in claim 1 wherein said area encompassing means includes a pair'of side guard sections spanned by said pivotal section. each side guard section includes a bore. said pivotal section including a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means. and said first and second abuttingly stopping means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last-mentioned end.

5. A guard for machinery comprising means for at least partially encompassing an area into which might be placed the hand of a'workensaid area encompassing means includes a pivotal section, means mounting said pivotal section for pivotal movement about a generally horizontal axis, means for restricting the pivotal movement of said pivotal section during its pivoting movement in a direction away from said area said area encompassing means includes a pair of side guard sections spanned by said pivotal section, each side guard section includes a bore, said pivotal section including a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, said restricting means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last mentioned end, said abutment means of said one end is an arm carried thereby disposed transverse to the axis of said rod, and said abutment means of said last-mentioned side guard is disposed in the path of pivotal movement of said arm results in the aforementioned restricted pivotal movement of said pivotal section.

6. The guard as defined in claim 5 including means for precluding pivotal movement of said section beyond a certain position in a direction toward said area, and said precluding means is other abutment means carried by said last-mentioned side guard disposed in the path of pivotal movement of said arm whereby contact between said other abutment means and said arm results in the aforementioned precluded pivotal movement of said section beyond said certain position.

7. A guard for machinery comprising means for at least partially encompassing an area into which might be placed the hand ofa worker, said area encompassing means includes a pivotal section, means mounting said pivotal section for pivotal movement about a generally horizontal axis, first means for abuttingly stopping the pivotal movement of said pivotal section beyond a certain position during its pivoting movement in a direction away from said area, and second means for biasing said pivotal section in a direction away from said certain position.

8. The guard as defined in claim 1 wherein said area encompassing means includes a pair of side guard sections spanned by said pivotal section, each side guard section includes a bore, said pivotal section including a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, and said first and second abuttingly stopping means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last-mentioned end.

9. The guard as defined in claim 8 including means for biasing said pivotal section to said certain position.

10. The guard as defined in claim 8 wherein said abutment means of said one end is an arm carried thereby disposed transverse to the axis of said rod, and said abutment means of said last-mentioned side guard is disposed in the path of pivotal movement of said arm whereby contact between said abutment means and said arm results in the aforementioned restricted pivotal movement of said pivotal section.

11. A combination comprising a machine bed, a bolster plate adapted to receive a die thereon, means for guiding said bolster plate into and out of a work area into which might be placed the hand of a worker, means for at least partially encompassing said work area, said area encompassing means includes a pivotal section, means mounting said pivotal section for pivotal movement about a generally horizontal axis, first means for abuttingly stopping the pivotal movement of said pivotal section beyond a certain position during its pivoting movement in a direction toward said area, and second means for abuttingly stopping the pivotal movement of said pivotal section during its pivoting movement in a direction away from said area.

12. The combination as defined in claim 11 wherein said work area encompassing means includes a pair of side guard sections spanned by said pivotal section. each side guard section includes a bore, said pivotal section includes a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, and said first and second abuttingly stopping means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last-mentioned end.

13. The combination as defined in claim 11 including means for precluding pivotal movement of said pivotal section beyond a certain position in a direction toward said work area.

14. A combination comprising a machine bed, a bolster plate adapted to receive a die thereon, means for guiding said bolster plate into and out of a work area into which might be placed the hand of a worker, means for at least partially encompassing said work area, said area encompassing means includes a pivotal section, means mounting said pivotal section for pivotal movement about a generally horizontal axis, means for restricting the pivotal movement of said pivotal section during its pivoting movement in a direction away from said area said work area encompassing means includes a pair of side guard sections spanned by said pivotal section, each side guard section includes a bore, said pivotal section includes a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, said restricting means is defined by cooperative abutment means'carried by at least one of said ends and the side guard section journalling said last-mentioned end, said abutment means of said one end is an arm carried thereby disposed transverse to the axis of said rod, and said abutment means of said last-mentioned side guard is disposed in the path of pivotal movement of said arm whereby contact between said abutment means and said arm results in the aforementioned restricted pivotal movement of said pivotal action.

15. The combination as defined in claim 14 means for precluding pivotal movement of said section beyond a certain position in a direction toward said area, and said precluding means is other abutment means carried by said last-mentioned side guard disposed in the path of pivotal movement of said arm whereby contact between said other abutment means and said arm results in the aforementioned precluded pivotal movement of said section beyond said certain position. 

1. A guard for machinery comprising means for at least partially encompassing an area into which might be placed the hand of a worker, said area encompassing means includes a pivotal section, means mounting said pivotal section for free pivotal movement about a generally horizontal axis, first means for abuttingly stopping the pivotal movement of said pivotal section beyond a certain position during its pivoting movement in a direction toward said area, and second means for abuttingly stopping the pivotal movement of said pivotal section during its pivoting movement in a direction away from said area.
 2. The guard as defined in claim 1 wherein said pivotal section has upper and lower portions, and said mounting means pivotally mounts said upper portion whereby said lower portion is stopped by said first and second abuttingly stopping means in said directions toward and away from said area.
 3. The guard as defined in claim 1 wherein the first and second abuttingly stopping means combiningly stop the pivotal movement of said section at generally 15*.
 4. The guard as defined in claim 1 wherein said area encompassing means includes a pair of side guard sections spanned by said pivotal section, each side guard section includes a bore, said pivotal section including a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, and said first and second abuttingly stopping means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last-mentioned end.
 5. A guard for machinery comprising means for at least partially encompassing an area into which might be placed the hand of a worker, said area encompassing means includes a pivotal section, means mounting said pivotal section for pivotal movement about a generally horizontal axis, means for restricting the pivotal movement of said pivotal section during its pivoting movement in a direction away from said area said area encompassing means includes a pair of side guard sections spanned by said pivotal section, each side guard section includes a bore, said pivotal section including a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, said restricting means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last-mentioned end, said abutment means of said one end is an arm carried thereby disposed transverse to the axis of said rod, and said abutment means of said last-mentioned side guard is disposed in the path of pivotal movement of said arm results in the aforementioned restricted pivotal movement of said pivotal section.
 6. The guard as defined in claim 5 including means for precluding pivotal movement of said section beyond a certain position in a direction toward said area, and said precluding means is other abutment means carried by said last-mentioned side guard disposed in the path of pivotal movement of said arm whereby contact between said other abutment means and said arm results in the aforementioned precluded pivotal movement of said section beyond said certain position.
 7. A guard for machinery comprising means for at least partially encompassing an area into which might be placed the hand of a worker, said area encompassing means includes a pivotal section, means mounting said pivotal section for pivotal movement about a generally horizontal axis, first means for abuttingly stopping the pivotal movement of said pivotal section beyond a certain position during its pivoting movement in a direction away from said area, and second means for biasing said pivotal section in a direction away from said certain position.
 8. The guard as defined in claim 1 wherein said area encompassing means includes a pair of side guard sections spanned by said pivotal section, each side guard section includes a bore, said pivotal section including a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, and said first and second abuttingly stopping means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last-mentioned end.
 9. The guard as defined in claim 8 including means for biasing said pivotal section to said certain position.
 10. The guard as defined in claim 8 wherein said abutment means of said one end is an arm carried thereby disposed transverse to the axis of said rod, and said abutment means of said last-mentioned side guard is disposed in the path of pivotal movement of said arm whereby contact between said abutment means and said arm results in the aforementioned restricted pivotal movement of said pivotal section.
 11. A combination comprising a machine bed, a bolster plate adapted to receive a die thereon, means for guiding said bolster plate into and out of a work area into which might be placed the hand of a worker, means for at least partially encompassing said work area, said area encompassing means includes a pivotal section, means mounting said pivotal section for pivotal movement about a generally horizontal axis, first means for abuttingly stopping the pivotal movement of said pivotal section beyond a certain position during its pivoting movement in a direction toward said area, and second means for abuttingly stopping the pivotal movement of said pivotal section during its pivoting movement in a direction away from said area.
 12. The combination as defined in claim 11 wherein said work area encompassing means includes a pair of side guard sections spanned by said pivotal section, each side guard section includes a bore, said pivotal section includes a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, and said first and second abuttingly stopping means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last-mentioned end.
 13. The combination as defined in claim 11 including means for precluding pivotal movement of said pivotal section beyond a certain position in a direction toward said work area.
 14. A combination comprising a machine bed, a bolster plate adapted to receive a die thereon, means for guiding said bolster plate into and out of a work area into which might be placed the hand of a worker, means for at least partially encompassing said work area, said area encompassing means includes a pivoTal section, means mounting said pivotal section for pivotal movement about a generally horizontal axis, means for restricting the pivotal movement of said pivotal section during its pivoting movement in a direction away from said area said work area encompassing means includes a pair of side guard sections spanned by said pivotal section, each side guard section includes a bore, said pivotal section includes a rod having opposite terminal ends each received in one of said bores whereby said bores and ends define said pivotal mounting means, said restricting means is defined by cooperative abutment means carried by at least one of said ends and the side guard section journalling said last-mentioned end, said abutment means of said one end is an arm carried thereby disposed transverse to the axis of said rod, and said abutment means of said last-mentioned side guard is disposed in the path of pivotal movement of said arm whereby contact between said abutment means and said arm results in the aforementioned restricted pivotal movement of said pivotal action.
 15. The combination as defined in claim 14 means for precluding pivotal movement of said section beyond a certain position in a direction toward said area, and said precluding means is other abutment means carried by said last-mentioned side guard disposed in the path of pivotal movement of said arm whereby contact between said other abutment means and said arm results in the aforementioned precluded pivotal movement of said section beyond said certain position. 